nir: Relax opt_if logic to prevent re-merging 64bit phis for loop headers

[mesa.git] / src / compiler / nir / nir_opt_large_constants.c

diff --git a/src/compiler/nir/nir_opt_large_constants.c b/src/compiler/nir/nir_opt_large_constants.c
index 7e293ba2c5e6d4950ec1b863b4fbc37a759e412c..860078edcb5b53cbd79f74490c32179121b47007 100644 (file)
--- a/src/compiler/nir/nir_opt_large_constants.c
+++ b/src/compiler/nir/nir_opt_large_constants.c
@@ -92,9 +92,11 @@ build_constant_load(nir_builder *b, nir_deref_instr *deref,
    if (load->dest.ssa.bit_size < 8) {
       /* Booleans are special-cased to be 32-bit */
       assert(glsl_type_is_boolean(deref->type));
+      assert(deref_size == num_components * 4);
       load->dest.ssa.bit_size = 32;
       return nir_b2b1(b, &load->dest.ssa);
    } else {
+      assert(deref_size == num_components * bit_size / 8);
       return &load->dest.ssa;
    }
 }
@@ -174,14 +176,15 @@ nir_opt_large_constants(nir_shader *shader,
    /* This pass can only be run once */
    assert(shader->constant_data == NULL && shader->constant_data_size == 0);
 
-   unsigned num_locals = exec_list_length(&impl->locals);
-   nir_index_vars(shader, impl, nir_var_function_temp);
+   unsigned num_locals = nir_function_impl_index_vars(impl);
 
-   if (num_locals == 0)
+   if (num_locals == 0) {
+      nir_shader_preserve_all_metadata(shader);
       return false;
+   }
 
    struct var_info *var_infos = ralloc_array(NULL, struct var_info, num_locals);
-   nir_foreach_variable(var, &impl->locals) {
+   nir_foreach_function_temp_variable(var, impl) {
       var_infos[var->index] = (struct var_info) {
          .var = var,
          .is_constant = true,
@@ -196,6 +199,19 @@ nir_opt_large_constants(nir_shader *shader,
     */
    nir_foreach_block(block, impl) {
       nir_foreach_instr(instr, block) {
+         if (instr->type == nir_instr_type_deref) {
+            /* If we ever see a complex use of a deref_var, we have to assume
+             * that variable is non-constant because we can't guarantee we
+             * will find all of the writers of that variable.
+             */
+            nir_deref_instr *deref = nir_instr_as_deref(instr);
+            if (deref->deref_type == nir_deref_type_var &&
+                deref->mode == nir_var_function_temp &&
+                nir_deref_instr_has_complex_use(deref))
+               var_infos[deref->var->index].is_constant = false;
+            continue;
+         }
+
          if (instr->type != nir_instr_type_intrinsic)
             continue;
 
@@ -225,6 +241,9 @@ nir_opt_large_constants(nir_shader *shader,
 
          if (dst_deref && dst_deref->mode == nir_var_function_temp) {
             nir_variable *var = nir_deref_instr_get_variable(dst_deref);
+            if (var == NULL)
+               continue;
+
             assert(var->data.mode == nir_var_function_temp);
 
             struct var_info *info = &var_infos[var->index];
@@ -250,6 +269,9 @@ nir_opt_large_constants(nir_shader *shader,
 
          if (src_deref && src_deref->mode == nir_var_function_temp) {
             nir_variable *var = nir_deref_instr_get_variable(src_deref);
+            if (var == NULL)
+               continue;
+
             assert(var->data.mode == nir_var_function_temp);
 
             /* We only consider variables constant if all the reads are
@@ -300,6 +322,7 @@ nir_opt_large_constants(nir_shader *shader,
    }
 
    if (shader->constant_data_size == 0) {
+      nir_shader_preserve_all_metadata(shader);
       ralloc_free(var_infos);
       return false;
    }
@@ -330,6 +353,9 @@ nir_opt_large_constants(nir_shader *shader,
                continue;
 
             nir_variable *var = nir_deref_instr_get_variable(deref);
+            if (var == NULL)
+               continue;
+
             struct var_info *info = &var_infos[var->index];
             if (info->is_constant) {
                b.cursor = nir_after_instr(&intrin->instr);
@@ -348,6 +374,9 @@ nir_opt_large_constants(nir_shader *shader,
                continue;
 
             nir_variable *var = nir_deref_instr_get_variable(deref);
+            if (var == NULL)
+               continue;
+
             struct var_info *info = &var_infos[var->index];
             if (info->is_constant) {
                nir_instr_remove(&intrin->instr);